At present, dry powder inhalers available have many forms of structure, but there are three main problems like: firstly, the low inhalation rate, which is, after the research on it, only 8˜16% of the drug granule is delivered to airways and lungs; secondly, the dry powder being easily blown out of the appliance, in case when breathing out into the mouthpiece, around where there are some dry powders for the inhaler to be breathed in, especially, the elderly and young children will often fail to control their expiration so as to blow out the dry powder; and thirdly, some mouthpieces are not easily cleaned, and particles of powder residue that have accumulated on the mouthpiece might cause cross inflection.